Current interrupter



Jan. 13. 1925.

c. E. BENNETT CURRENT INTERRUPTER Original Filed June 24, 1919 2Sheets-Sheet l NVENTOR.

CH3/u ES EJSENNE T T Jan, 13. '1925.

NTT

CURRENT INTERRUPTER original Filed Juge 24, 1919 2 Sheets-Sheet 2Patented dan. i3, 1925.

tenue CHARLES E. BENNETT, OF ATLANTA, GEORGIA, ASSIGNOR, 'BY DIRECT ANDMESNE ASSIGNMENTS, TO BALT MANUFACTURING COMPANY, OF ATLANTA, GEORGIA, A

CORPORATION OF GEORGIA.

CURRENT INTERRUPTER.

Application led June 24, 1919, Serial No. 306,383. Renewed December 11,1923.

To all whom t may oon-cern.'

Be it known that I, CHARLES E. BENNETT. a citizen of the United Statesot America, residing in the city of Atlanta, county ot Ful-- ton, andState ot Georgia, have invented certain new and useful improvements inCur rent Interrupters, of which the following is a speciiication.

My invention relates to automatic current interrupters, and particularlyto a device of the general type shown in my co-pending applications Ser.Nos. 207,771 and 247,826, led respectively on December 13, 1917, andAugust 1, 191.8, the object of my present inventio-n being to improvethe construction and operation ot the device in certain teatureshereinafter described or shown in the accompanying drawings, in whichFig. 1 is a vertical section through an apparatus in which my inventionis embodied in one form;

Figs. 2, 3 ande are similar views drawn to a smaller scale andillustrating the operation of the apparatus; and

Fig. 5 is a side elevation ot a modified construction.

The apparatus here illustrated comprises certain main features ofresemblance to that shown in my co-pending applications above referredto, but differing therefrom in certain particulars hereinafter pointedout. A suitable container or tank 1() is partially filled by a body otliquid 11-12 constituting a low resistance electrolyte Aot suitablecapacity which may be varied to suit the needs of jthe particularinstallation. Passing through a bushing in the head of the tank orcontaineris a tube of insulating material, the lower portion 13 ot whichdips into the electrolyte and extends downward therein to a pointadjacent the bottom of the tank, while the upper portion 5 of the tubeprojects above the tank and is provided with skirts 4 after the Jfashionof a post insulator. Enclosing the upper end ot the tubing is a metalcap 61, through which passes a conductor 6 in the form of a pipe, at thelower end of which is mounted an electrode 7 the pipe being adjustablethrough its lock nut 62, to bring the electrode 7 into contact with theelectrolyte which rises in the tube. The pipe 6 is open at its upper endwhile a hole 71 in its wall establishes communication between theinterior of the pipe and the eXpan sion lchamber .141 which lies abovethe electrolyte in the tube 13. The head 101 ot' the tank carries an arm102 which supports the pin insulator 3. A lead 1 from the power line issecured to the insulator cap 31, through which passes the adjustablebase rod 21 of one branch ot the combined sphere and horn gap 22, theother branch ot which is secured to the cap 61 of the insulating tube5-13.

A gauge 9 let into the tank 10 indicates the liquid level in the tank.The electrolyte 11-12 is grounded in any suitable way, as by aconnection 103 to the tank, where the latter is of metal.

The operation ot the apparatus is as follows: Assuming an arc to havebeen established at the horn gap 2 2 by excessive voltage, such asaccompanies a stroke of light-ning, the normal line voltage maintainsthe arc and grounds the power current through (i, 7, 12, 11 and 103.This arc is automatically broken and normal conditions reestablished, asshown in Figs. 2, 3 and 1- and explained as follows: The area of contactbetween the electrode 7 and electrolyte 12 in the tube 13 is small,since the electrode is adjusted merely to touch, or only slightly dipinto, the electrolyte. The heating eii'ect of the current is thereforeconcentrated at this point and not only is the air within the chamber 14rapidly heated, but the electrolyte in contact with the electrode 7 isimmediately vaporized and expanded. It the electrolyte is water, steamis formed. The resultant pressure in the chamber 14 forces downward theelectrolyte in the tube 13 with the result that the arc X (Fig. 3) israpidly lengthened downward until it breaks and the ground connection isthereby interrupted. The expanded air and evaporated electrolytethereupon partially condense in the chamber 14 and partially escapethrough the pipe 6. whereupon the electrolyte from the tank promptlyrises again in the tube 13 and reestablishes contact with the electrode7. Normal conditions are thus reinstated. Another importantcharacteristic of the present apparatus is the condenser actionobtained. It will be noted that the electrolyte within the tube 13 isseparated by the insulating wall of the latter from the surroundingelectrolyte in the tank 10. The current enters the electrolyte in theupper l5, tically n il 40 Qhyfthe.; trap'ijed vapor.

, 5011 much the corr 60N-usual three linefwires,4 associated with a thecurrent enters the electrolyte in the tank at the lower end of thetube," 4Inothei words, the electrolyte in the upper 'portion ot' thetube.car ries current at a higher voltage than that of the electrolytein the tank -l0,surrounding,the tube,.a nd thevoltage `differentialdrops` progressively fas the lower end of die tube is ap'proachedA4'l"liec n denseraction;is` therefore most marked in the Yupper.reachesof th tube,1,and is' pracitslowen euch llowevenr the condenser actilpnis niuch greater' than isfthe case oi thewusiial condenser sincetheelectrolyte within the tube-which forinswone v`plate ot ythecondenser-is being constantly drained to ground 01E-,its kcurrentthrough Qtheresistance of. the electrolyte in tlie lower portion oftheinbe'and inthe tank.

On, tlie downward displacement oi? -the velectrolyte* in the tube bytheftlra'ppedwvapfor.

thehcondenser action is doubtless modified andfis believed. tobe1increased since the voltagez'at thepoint atylvhich the current entersthe. lvapor is ,doubtless 1nuclrirreaterl than t'li'atloi:`theeelectrolyte lin the tankbv reason ofthe" greater 'current drop,incident to the Aincreased resistance interposed by the vapor. fact,however, is not iisiially of imporltance since ,the high frequencycharge is ori din arilyidrained ,throngh the arrester before `1` thedownward. displacement of vthe electro- '.liftezwithin they tiibeoecurs;and it is not nn- ,tile,thewiflogni` oifythe norn'ial rline current bc-Ycorines,effec'tivezto vaporize the ielectrolyte in y y hetube that thelatter is forced downward e Conseqi'iently dur ling the discharge ofLthehigh freqiiency c ur- ,lrientkthe condeneer faction isV that.incident to the i'i'illeljefctrolyte:plat l titsy normal level, landsen l l Y submerged 'D ortion of Ythe Afiinsnlating tube. Ii", however,l1th edhiirh` firjequency current 'should persist,` fa, instancevbyreasonof a succession of lightning didm'aea whiehfina y y lastf for asnas eco1-id, ory a resonance condition oneven renterE lduration onthe Iline, the confdenser effect is1 still attained although the ,fwatellegwithin the tube'may be Vdriven downward.f This is due to the fact thatthe te apo/rl whichhasreplaced the electrojte lsfstill 'at aiiiuchhigher voltage Athan the' siirroiindi. electrolyte lof the tank.y

'11n Fig, 'l'f'hl te shown? three interruiiters esponclinggaps l5 of thefsingle :tank 16k 1In'other respectsi the con- ,-fstructionandy'operation are ident-ical with thatj'nstfdesribedw l Y y, 'Itwillbenoted that in 'the "present ar- .65 rangement I have .eliminated thesubmerged rated from the electrolyte in `the hand Iliave retainedthea'dvzi'ntage of the y constructionshown in Serial No. A247,826wherein the Vinsula'ting'[tube in tvliichftlie arc is 'lcgrineddips,into the electrolyte Vfin the ljaiil which 'eii'erctkvelyycools lietub-efand preventshl at injniy thereto while the: areN Thelplarticiilarconstruction' isniaintaiiied. y l of thetube fg-lfand of 'p'ipefl'ead'6to the electrode'as'well as the ventof the chainber 14 'and the mannerof 'sfiippoiitiigj the arrangement and ,constitute iiiipov'einnts overmyl. former constructions, but are Vneyertireless subject to muchfurther modification without Vdeparting from whatI claim as myinvention.V i Y.

Ic'l'aim: re: Y l. 'Inma device of the class described, a container, aconducting fluid' within" the container, an' iii'siiliat`i1ig-tiibedinpingjnto ySaid fluid and open thereto, but substantial? lyclosedatits iipp'erendQand anfelec'trlde ingang-h in@ idpdf- 'the@manier- "iiiiu gdipe ping 'atnit-sl-ower'rjend 4into :said V"iiiiid"and opentheretq butisnbistantially` closed at its npperentl,l and anelectrode passing :down l througlisaid Atiibe 'iiito ciiirentlow Lasso-Aciation with the Iupper in' the tube, sfaid'ltube affordingatfitsnpperclosed nortion'a ,pressure "chamber in ZWliich vapor"istrapped and depresses Ythe fluid in the tube away iii'oin theelectrdeon`discharge,"thronghthe"circuit. v V il 3.111 a vdevice of the classdescribedg a container, a ylconducting iliiid vwithii1-"the r`container,an insulating 'tube passing through the top 'ofthe container. and V,dip-`pingrtnits lower end sf'aid 'fluidfand openy thereto,butfsubjsta'tially A closed at i its tnpjoerm'en'd, andanelectrodefijassing doyvn1 through saidy Y tube ,iiit'o n current-flowassociation with thefiijperfpoition 'of'fthe Huid in, the tiibe,saiditu'be aifrding at,y its upper closed portionganj'pijessui'ed`chziihber `in which vapor is trapped and 'den eSSflSfLthe fluildfjinthe tube a"a`y from the'electrode on disharge thfogh the aimait,*'tlguiei-fwiui an alr gap terminal mounted onthe upper ico LLI

end yof the tube and electrically connected to the electrode.

4. In a device of the class described, a container, a conducting fluidwithin the container, an insulating tube passing through the top of thecontainer and dipping at its lower end into said fluid and open thereto,but substantially closed at its upper end, and an electrode passing downthrough said tube into current-fi'ow associa- .tion with the upperportion of the fluid in the tube, said tube affording at its upperclosed portion a pressure chamber in which vapor is trapped anddepresses the fluid in the tube away from the electrode on dischargethrougn the circuit, together with an air gap terminal mounted on theupper end of the tube and electrically connected to the electrode, incombination with a bracket mounted on the container, and a secondary gapterminal mounted thereon and cooperating with the gap terminal mountedat the upper end of the tube.

5. In a device of -the class described, a container, a conducting fluidwithin the container, an insulating tube passing through the top of thecontainer and dipping at its lower end into said fluid and open thereto,but substantially closed at its upper end, and an electrode passing downthrough said tube into current-flow association with the upper portionof the fluid in the tube, said tube affording at its upper closedportion a pressure chamber in which vapor is trapped and depresses thefluid in the tube away from the electrode on discharge through thecircuit, together with means for venting the pressure chamber in thetube to prevent building up of excessive pressure therein.

6. In an automatic current interrupter, a reservoir, an electrolytetherein, an insulating tube dipping into the electrolyte and openthereto, and a conductor arranged in current flow association with theelectrolyte within the tube to cause the current to pass therethroughand thus to at least partially vaporize the same and draw an arc withinthe tube on the operation of the arrester, said conductor being a pipethrough `which the upper portion lof the tube is vented, substantiallyas described.

7. In a protective ground connection, a container, an electrolytetherein, an insulating tube extending into the electrolyte and chilledthereby, a pressure chamber above the level of the electrolyte in thetube, and means for leading current tothe electrolyte in the tube to atleast partially vaporize the same on discharge through the apparatus andcause vapor to accumulate in the pressure chamber, depress theelectrolyte in the tube and draw an arc under vapor pressure in thesubmerged and chilled areaof the tube.

8. A protective device comprising a resistance liquid condenser, meansfor leading current to one plate of the condenser, and means fortrapping vapor generated by the flow oi current through said plate todisplace its liquid and thereby interp'ose a vapor resistance to theflow of currents.

9. A protective device comprising a liquid resistance condenser, meansfor leading current to one plate of the condenser, and means fortrapping vapor generated by the flow of current through said plate todisplace its liquid and thereby substitute vapor under pressure 'torsatleast portion of said liquid plate 'of the condenser.

In testimony whereof I have signed my name to this specification.

CHARLES E. BENNETT.

